The present invention relates to magnetic disc memory apparatus including at least one magnetic head to read from or write in the corresponding track of a rotating magnetic disc, a carriage carrying said magnetic head, and guide rod means guiding translation of the carriage to position the magnetic head onto a desired track of the magnetic disc.
In a fixed disc memory apparatus or a floppy disc memory apparatus, the read and/or write magnetic head must be accurately positioned on a desired track on the magnetic disc to read from or write in the track. Thus, the carriage which carries the magnetic head is driven by suitable means, e.g. a stepper or pulse motor, to translate radially to the magnetic disc. As the magnetic head must be positioned accurately on the desired track of the magnetic disc, the carriage must translate accurately relative to the disc. When the guide rod means is a pair of parallel guide members, the guide members must be precisely parallel with each other to perform accurte and smooth translation. Further, the two guide members must be precisely similar in dimension. Production of such an arrangement is difficult and necessitates high cost.